1. Field of the Invention
The present invention relates to an image forming apparatus, which records images on a recording paper, such as a copying machine, a facsimile machine, a printer and a multifunctional machine, which integrates functions of these apparatuses.
2. Description of Background Information
Conventionally, a copying machine, a facsimile machine, a printer and a multifunctional machine, which is a copying machine to which a facsimile function and/or a printer function are/is added (hereinafter, referred to as xe2x80x9cimage forming apparatusxe2x80x9d in general) are provided with a power supply having a predetermined electric capacity, and an electric power used by each function is determined so that various functions can be executed within the predetermined electric power capacity of the power supply.
However, in the conventional technology, there are problems as described below. Recently, the number of functions requested for the image forming apparatus mentioned above is increased. In addition, it is often required that plural functions are processed in parallel.
For example, in a copying machine, a sophisticated (multifunctional) copying machine is realized, in which an automatic document feeding function (hereinafter, referred to as xe2x80x9cADF operationxe2x80x9d), which feeds an original from an original document holder, passes the original over a platen glass and conducts the original toward a dispatcher, a double-sided recording paper feeding function (hereinafter, referred to as xe2x80x9cADU operationxe2x80x9d), which feeds a recording paper automatically turned over to perform double-sided recording, and a staple function, which automatically staples recorded papers in the apparatus.
In a facsimile machine, an ADF function, a broadcast function, a time programmed transmission/reception function and an Internet function are added in addition to a transmission/reception function.
In a printer, a high speed (acceleration) function, a USB function and a wireless driving function are added.
In a multifunctional machine, all of the above-described functions are integrated or selectively added. Further, a color recording function is added to all the above-described image forming apparatuses.
Thus, the progress of multifunctionality and sophistication of functions increase an electric power required for the image forming apparatus. Further, when simultaneous use of plural functions are requested, the electric power larger than the predetermined capacity of the electric power supply of the machine is required. Accordingly, to respond to the requirement, the capacity of the electric power supply of the machine is usually increased.
However, an electric power supplied by an electrical outlet provided at an office or a usual home has an upper limit. Therefore, there is a limit to increase an electric capacity of the power supply of the machine. When the electric capacity of the machine exceeds the limit, a separately provided special power supply is required to fulfill the requirement. In this case, a user must purchase a dedicated power supply in addition to the machine itself. As a result, it becomes a problem that the user is forced to have more than necessary economic burden and to prepare a space for installation.
Accordingly, the object of the present invention is to provide an image forming apparatus that can realize a priority process and a parallel (concurrent) process of requested plural functions without increasing an electric source capacity of the apparatus, and without increasing user""s economic burden, even when the requested functions are increased and plural functions are requested to be processed in parallel (concurrently).
Image forming equipment of the present invention comprises a power supply with preset upper limit of electric energy that supplies electric power to the equipment, the first function that operates on the first electric energy, and the second function that operates on the second electric energy wherein, at the request of parallel processing of the first function and the second function, either the first function or the second function is processed in priority when total of the electric energy required by the first function and the second function exceeds the upper limit capacity of the power supply and they are processed in parallel when the total energy does not exceed the upper limit capacity.